(19)

(11)

EP 3 821 044 A1

(12)

(43) Date of publication: 19.05.2021 Bulletin 2021/20 (21) Application number: 19744823.6 (22) Date of filing: 12.07.2019

(51) International Patent Classification (IPC):  C22B 9/00(2006.01) B03C 1/32(2006.01) C22B 21/06(2006.01) (86) International application number: PCT/GB2019/051967 (87) International publication number: WO 2020/012199 (16.01.2020 Gazette 2020/03)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME Designated Validation States: KH MA MD TN (30) Priority: 12.07.2018 GB 201811413 (71) Applicant: The University of Birmingham Birmingham B15 2TT (GB)	(72) Inventor: CAI, Biao Birmingham Edgbaston Birmingham B15 2TT (GB) (74) Representative: Chapman, Paul Gilmour  Marks & Clerk LLP 40 Torphichen Street Edinburgh EH3 8JB Edinburgh EH3 8JB (GB)